Refrigerating apparatus



Oct. 17, 1933. MOCORMACK 1,931,323

REFRIGERATING APPARATUS Original Filed Aug. 30, 1930 2 Sheets-Sheet l 58 CllNgEfiZOR Oct. 17, 1933. A. A. M CURMACK xsmms'nA-rme APPARATUS- 2 Sheets-Sheet 2 Original Filed Aug. 30, 1930 \\\\\\\\\\\\\\\\\\\\\\\\KAY INVENTOR -M:;&.%W W A'ITORNEF Patented Oct. 17, 193

. 1,931,323 'aermcaaa'rme mam-ms Alex A. 'McCoi-mack,

Fl'igi poratlon of Ohio Application August 30, 1930, Serial Dayton, Ohio, assignor to daire Corporation,

Dayton, Ohio, a cor- Renewed November 3, 1932 9 Claim.

This invention relates to refrigerating apparatus of the compression type, and more particularly to motor-compressor-condenser units for use in refrigerating apparatus of such type.

3 One of the objects of the present invention is to provide improved means for supplying lubricant to moving elements of the compressor mechanism from a reservoir and to return said lubricant to said reservoir.

Another object is -to, arrange the aforesaid means in such a manner that lubricant in any appreciable amount is prevented from being circulated throughout the refrigerating system.

. Another object is to provide a gas tight casing for housing the compressor and its driving motor and to employ said casing for storing a quantity of liquid refrigerant and a quantity of lubricant.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the-present invention is clearly shown.

In the drawings:

Fig. 1 is a view, partly in cross section and 5 partly diagrammatic, of a refrigerating apparatus embodying features of my invention;

Fig. 2 is a view in cross section of a portion of the apparatus shown in Fig. 1 the view being taken on the line 2-2 of Fig. 1; and I Fig. 3 is a'fragmentary view in cross section taken along the line 3-3 of- Fig. 2.

Heretofore in refrigerating compressing units of the sealed-in type, difficulty has been encountered for the reason that where a casing encloses the compressor and motor and is provided with an outside condenser, a slight amount of refrigerant is condensed in the casing before a the gaseous refrigerant reaches the condenser. Where a body of oil'is provided in the bottom of this casing for the lubrication of the apparatus, the refrigerant thus condensed flows to the body of oil and gradually builds up such a large body of liquid refrigerant that the oil is displaced from its normal position in the casing and .is thus prevented from circulating to the moving parts of the mechanism. Ac'cording to this invention, this and other difficulties are avoided by providing a sump in the casing of sufficient capacity and correct design, that all of the liquid refrigerant condensed in the casing and also in the outside condenser itself can be discharged into the sump where the liquid refrigerant and the lubricant maintain their proper zones for the proper operation of the mechanism. 55 The liquid refrigerant from this sump is (then circulated through the evaporator and returned in an evaporated condition to the regular inlet of the compressing unit.

Referring to the drawings, the numeral designates in general a motor compressor unit 60 comprising a gas tight casing 21 which forms a compression chamber 22 in which is located a compressor 24 and a driving motor 25 operatively connected with said compressor by means of a shaft 28. The compressor is adapted to supply as liquid refrigerant to an evaporator for providing refrigeration at a desired place. The compressor withdraws the gaseous refrigerant from the evaporator through a conduit 32, compresses the gaseous refrigerant and delivers it to an out- 70 sidecondenser 35, preferably air-cooled, through an outlet passage 3'1 provided in the gas space of the compression chamber 22. The condenser condenses the gaseous refrigerant and delivers it to a reservoir or sump formed in the bottom 15 of the casing 21. The reservoir 40 provides a receiver forstoring a body of liquid refrigerant. For the purpose of illustration 1, have indicated the liquid refrigerant level M42. The reservoir 40 also provides a storage space'for a body of 80 lubricating oil used for lubricating moving elements of the compressorin ,a manner hereinafter described. For the purpose of illustration I have shown the level of lubricating oil at 45. The motor compressor unit delivers liquid refrigerant 35 from the reservoir 40 to the evaporator 30 under the control of an expansion valve 47 through a supply conduit 49 having a connection 50-with the casing 21 below the level of liquid refrigerant. A thermostat 52 is connected to the rear end of 90 the evaporator and is operatively connected to a switch 55. The'switch 55 connects the motor 25 with the power mains 58 and is arranged for controlling the starting and stopping of the motor 25 in response to the orator 30. A'motor driven fan 60'for cooling the condenser 35 is connected in parallel with the motor 25' and is controlled by the switch 55.

Referring more in detail to the drawings, the casing 21 is formed in three parts, namely, a lower member 62, an intermediate member 64 and a top member 65. The lower member 62 is provided with an upwardly extending boss 6'? having a bore 68 which receives a bushing 69 which provides a bearing 70 for the lower end of the shaft 28. The intermediate member 64 is provided with an integrally formed inwardly extending portion '72 which provides a bearing surface 74 for the upper part of the shaft 28. The portion '72 permits communication between the lower temperature of the evap- 5 and intermediate members through one or more openings 76. The lower and intermediate portions are secured together by screws 78 and the top member 65 is secured to the intermediate member by screws 80. Suitable gasket material is provided between the joints of the members 62, 64 and 65 to thus provide a gas tight or hermetically sealedc The motor 25 for driving the compressor 24 comprises a rotor and a stator 86. The compressor 24 comprises in general a cylinder secured to the boss 67 by screws 91. An oscillating sleeve 94 is adapted to be actuated within the cylinder 90 for compressing the gas. The sleeve 94 is adapted to be actuated by an eccentric 97 formed integrally with the shaft 28. The compressor is provided with an inlet passage 100 which extends through boss 67 and the wall of the sleeve 90 and leads to the compression space of the compressor. An outlet passage 102 leads to the compression chamber 22 whence the compressed gas passes through the outlet passage 37 provided in the top member 65 of the casing 21 to a condenser 35. Preferably the outlet passage 37 is provided with a check'valve 106 which permits the gas to pass therethrough but prevents return thereof.

In order to provide means for lubricating the moving elements of the compressor Ihave provided a lubricant pump 110 of the eccentric type. The pump is provided with an inlet passage 112 located below the level of lubricant and above the level of liquidrefrigerant. The pump 110 is adapted to build up a pressure in the space 115 formed in the boss 67 and to force the-lubricant through a passage formed in the central por' tion of the shaft 28 whence the lubricant is, delivered to lateral ports 122, 123, 124, and 126 in said shaft. The ports 122 and 123 serve to supply lubricant to the bearing 70 and the ports lubricant to the sleeve 94' 124 and 125 deliver while theport 126 allows lubricant to flow to the bearing 74. The lubricant thus circulated will return to the reservoir 40 by gravity.

' In the present embodiment I'have shown the liquid refrigerant as gravity than the lubricant. It is to be understood however, that the lubricant could be located below the liquid refrigerant by providing a liquid refrigerant of lighter specific gravity than the lubricant and by simply changing the position of the pump inlet 112 and the liquid refrigerant outlet 50.

In an apparatus of the type herein described there are-many advantages some of which are that lubricant and liquid refrigerant are stored in the motor compressor casing and that the lubricant which is used for lubricating moving elements of the system is prevented from entering the refrigerating system in any appreciable amount, and this is accomplished by providing the liquid refrigerant outlet on the casing below the level of liquid refrigerant and by connecting the condenser 35 in parallel with the casing 21. Thus, if lubricant should pass through the outlet 37 it would,be returned to the reservoir through the condenser 35, and might be dissolved in the liquid refrigerant would be circulated through the evaporator.

While the form of embodiment of the invengtion as herein disclosed, constitutes a preferred form, it is understood that other forms Imight be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

having a heavier specific j one end thereof only such lubricant as 1. Refrigerating'apparatus comprising in combination a casing, a compressor within said casing, a motor for driving said compresser within said casing, said casing providing a reservoir for a body of lubricating oil and for a body of liquid refrigerant, a condenser located outside said casing and having a connection with said casing for condensing the gaseous refrigerant discharged by said compressor and for delivering the condensed refrigerant to said reservoir, an evaporator connected on one end thereof "to the liquid refrigerant space in said casing and its other end leading to said compressor and means for delivering said lubricant to said compressor and returning said lubricant to said reservoir.

2. Refrigerating apparatus comprising in combination a casing, a compressor within and discharging into said casing, a motor for driving saidcompressor within said casing, said casing providing a reservoir for a body, of lubricating oil and for a body of liquid refrigerant, a condenser located outside said casing and having one end thereof connected to the gas space in said casing and its other end connected to said casing and leading to said reservoir for condensing the gaseous refrigerant discharged by the compressor into said casing and delivering it to said reservoir, an evaporator connected on one end thereof to the liquid refrigerant space in said casing and its other end leading to said compressor and a lubricating system'for delivering lubricant to said compressor and returning said lubricant to said reservoir.

3. Refrigerating apparatus comprising in combination a casing, a compressor within and discharging into said casing a motor for driving said compressor, said motor being located in said casing, said casing providing a reservoir for a body of lubricating oil and for a body of liquid refrigerant, a'condenser located outside said casing having one end thereof connected to the gas space in said .casing and, its other end connected to said casing below the level of refrigerant in said reservoir, an evaporator connected on one end thereof to the liquid refrigerant space in said casing and its other end leading to said compressor and means for delivering said lubricant to said compressor and returning it to said reser- V011. I

4. Refrigerating apparatus comprising in combination a casing, a compressor within said casing,'a motor for driving said compressor, said motor being located in said casing, said casing providing areservoir for a body of lubricating oil and for a body of liquid refrigerant, a con-e denser located outside said casing and having connected to the gas space in said casing and its other end connected to said casing below the level of refrigerant in said reservoir, an evaporator connected on one end thereof of the liquid refrigerant its other end leading to said compressor and a lubricant pump having an inlet below the level of lubricant in said casing for delivering said lubricant to saidcompressor and'returning it to said reservoir.

5. Refrigerating apparatus comprising in combination a casing, a compressor within said cas-' ing, a'motor for driving said compressor, said motor being located in said casing, said providing a reservoir for a body of liquid refrigerant and for a body I liquids being of a heavier specific gravity than the other, a condenser located outside said casing and having a connection with said casing for space in said casing and of lubricant, one of said.

and 1,5

casing condensing the gaseous refrigerant discharged by said compressor and for delivering the condensed refrigerant to said reservoir, an evaporator connected on one end thereof to the liquid refrigerant space in said casing and its other end leading to said compressor and means for delivering said lubricant to said compressor and for returning it to said reservoir.

6. Refrigerating apparatus comprising in combination a casing, a compressor within said casing, a motor for driving said compressor, said motcrbeing located in said casing, providing a reservoir for a body of liquid refrigerant and for a body of lubricant, said liquid refrigerant being of a heavier specific gravity than said lubricant, a condenser located outside said casingand having one end thereof connected to the gas space in said casing and its other end connected to said casing below the level of liquid refrigerant therein, an evaporator connected on one end thereof to the liquid refrigerant space in said casing and its other end leading. to said compressor and means for delivering said lubricant to said compressor and for returning it to said reservoir.

7. Refrigerating apparatus comprising in combination a casing, a compressor within said casing, a motor for driving said compressor in said casing, said casing providing a reservoir for a body of lubricant and a body of liquid refrigerant, said liquid refrigerant being of a heavier specific gravity than said lubricant, a-condenser located outside said casing and having a connection with said casing for condensing the gaseous refrigerant discharged by said compressor and for delivering the condensed refrigerant to said reservoir, an

said casing communication with said within said casing munication with said casing, in

evaporator connected on one end thereof to the liquid refrigerant space other end leading to said compressor, and means for delivering said lubricant to the compressor and'returning it to said reservoir.

, 8. Refrigerating apparatus comprising a motor-compressor-condense'r unit and an evaporator in refrigerant circulatingrelationship, said motor-compressor-condenser unit comprising a casing, a compressor within said casing, a motor within said casing driving said compressor, and a condenser located outside said casing and having one end thereof connected to the gas space in said casing and having its other end in open casing, and returning lubricant from said condenser to said casing, an evaporated refrigerant line delivering evaporated refrigerant from said evaporator to said unit, and a liquid refrigerant line delivering liquid'refrigerant from said unit to said evaporator.

9. Refrigerating apparatus comprising a motor-compressor-condenser unit and an evaporator in refrigerant circulating relationship,- said motor-compressor-condenser unit comprising a casing, a compressor within said casing, a motor driving said compressor; and a condenser located outside said casing and having one 'end thereof connected to the gas space in in said casing and its said casing and having its other end in open comwhich condenser all of the condensation of said refrigerant normally takes place and from which said other end the lubricant discharged from said casing into said condenser is returned. ALEX A. MCCQRMACK. 

